[PATCH V3 2/3] nvmet: get transport reference for passthru ctrl

[Chaitanya Kulkarni]

From: Christoph Hellwig <hch at lst.de>

Grab a reference to the transport driver to ensure it can't be unloaded
while a passthrough controller is active.

Fixes: c1fef73f793b ("nvmet: add passthru code to process commands")
Reported-by: Chaitanya Kulkarni <chaitanya.kulkarni at wdc.com>
Signed-off-by: Christoph Hellwig <hch at lst.de>
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni at wdc.com>
Reviewed-by: Logan Gunthorpe <logang at deltatee.com>
---
 drivers/nvme/target/passthru.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/nvme/target/passthru.c b/drivers/nvme/target/passthru.c
index 8bd7f656e240..dacfa7435d0b 100644
--- a/drivers/nvme/target/passthru.c
+++ b/drivers/nvme/target/passthru.c
@@ -517,6 +517,7 @@ int nvmet_passthru_ctrl_enable(struct nvmet_subsys *subsys)
 		subsys->ver = NVME_VS(1, 2, 1);
 	}
 
+	__module_get(subsys->passthru_ctrl->ops->module);
 	mutex_unlock(&subsys->lock);
 	return 0;
 
@@ -531,6 +532,7 @@ static void __nvmet_passthru_ctrl_disable(struct nvmet_subsys *subsys)
 {
 	if (subsys->passthru_ctrl) {
 		xa_erase(&passthru_subsystems, subsys->passthru_ctrl->cntlid);
+		module_put(subsys->passthru_ctrl->ops->module);
 		nvme_put_ctrl(subsys->passthru_ctrl);
 	}
 	subsys->passthru_ctrl = NULL;
-- 
2.22.1